NUCAPS Profiles are back in AWIPS

July 2nd, 2019 |

1200 UTC Soundings from KGYX (Grey Maine) on 2 July 2019 and 1600 UTC NUCAPS sounding from nearby, showing changes in the thermodynamics (Click to enlarge)

Back in late March 2019, the Cross-track Infrared Sounder (CrIS) suffered an anomaly such that the mid-wave portion of the electromagnetic spectrum (a part that includes channels sensitive to water vapor) was not scanned properly. Thus, NUCAPS soundings created from Suomi-NPP were lost (link). Today, NUCAPS soundings created using NOAA-20 (which has the same instruments as Suomi-NPP) began flowing into AWIPS. Data from shortly after 1500 UTC were the first to appear.

NUCAPS Soundings over the northeastern United States at 1629 UTC on 2 July 2019 (Click to enlarge)

NUCAPS profiles from NOAA-20 are processed somewhat differently than those from Suomi-NPP as far as latency: NOAA-20 NUCAPS profiles show up more quickly — typically within an hour of the observations time — in AWIPS than NPP NUCAPS profiles did. This is important because the thermodynamic information in these mid-afternoon observations is important in judging destabilization relative to morning soundings.

When Suomi NPP was launched, two independent sets of electronics were present on CrIS; the ‘A’-side set of electronics were used until March; the ‘B’-side electronics have been used since June, and mid-wave observations from Suomi-NPP’s CrIS are now available at this site. However, NUCAPS soundings are not yet being created from Suomi-NPP because the A-side and B-side electronics have different statistical behavior that must be accounted for in the Regression used to start the NUCAPS processing.

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